smartstring/ts/smartstring.domain.ts

export class Domain {
  public fullName: string;
  public level1?: string;
  public level2?: string;
  public level3?: string;
  public level4?: string;
  public level5?: string;
  public protocol?: string;
  public zoneName: string;
  // aliases
  public topLevel?: string;
  public domainName?: string;
  public subDomain?: string;
  public port: string;
  public nodeParsedUrl: URL;
  constructor(domainStringArg: string) {
    // lets do the node standard stuff first
    this.protocol = this._protocolRegex(domainStringArg);
    if (!this.protocol) {
      domainStringArg = `https://${domainStringArg}`;
    }
    this.nodeParsedUrl = new URL(domainStringArg);
    this.port = this.nodeParsedUrl.port;

    // lets do the rest after
    const regexMatches = this._domainRegex(
      domainStringArg.replace(this.nodeParsedUrl.pathname, '')
    );
    [this.level1, this.level2, this.level3, this.level4, this.level5] = regexMatches;
    this.fullName = '';
    for (const localMatch of regexMatches) {
      if (this.fullName === '') {
        this.fullName = localMatch;
      } else {
        this.fullName = localMatch + '.' + this.fullName;
      }
    }
    this.zoneName = [this.level2, this.level1].filter(Boolean).join('.');

    // aliases
    this.topLevel = this.level1;
    this.domainName = this.level2;
    this.subDomain = this.level3;
  }

  // helper functions

  /** */
  private _domainRegex(stringArg: string): string[] {
    const regexString =
      /([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}([a-zA-Z0-9\-\_]*)\.{0,1}$/;
    const regexMatches = regexString.exec(stringArg);
    if (!regexMatches) {
      return [];
    }
    const reversedMatches = [...regexMatches].reverse(); // make sure we build the domain from top level to subdomain
    reversedMatches.pop(); // pop the last element, which is, since we reversed the Array, the full String of matched elements
    const regexMatchesFiltered = reversedMatches.filter(function (stringArg: string) {
      return stringArg !== '';
    });
    return regexMatchesFiltered;
  }

  private _protocolRegex(stringArg: string): string | undefined {
    const regexString = /^([a-zA-Z0-9]*):\/\//;
    const regexMatches = regexString.exec(stringArg);
    if (regexMatches) {
      return regexMatches[1];
    } else {
      return undefined;
    }
  }

  private _portRegex(stringArg: string): string | undefined {
    const regexString = /^([a-zA-Z0-9]*):\/\//;
    const regexMatches = regexString.exec(stringArg);
    if (regexMatches) {
      return regexMatches[1];
    } else {
      return undefined;
    }
  }
}